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Problem with MapPolyline when zooming (blurred polyline)

Jul 27, 2015 at 1:40 PM
Edited Jul 27, 2015 at 2:23 PM
Hi,

I'm currently using the Xaml map control in a Windows Universal app. I'm facing the following problem:

Image

I added a Polyline to the map but with each zoom level the line gets more blurred. I used the Template from the Win RT example application and added just a converter which converts the source data structure containing all locations as BasicGeolocation to the LocationCollection class of the map control.

Greetings,
Sven
Coordinator
Jul 27, 2015 at 4:29 PM
I can't tell why this happens. A MapPolygon is just a Path that uses the Map's ViewportTransform for the Transform of its Data (i.e. the Geometry.Transform property). There seems to be some kind of visual "optimization" applied by Windows Runtime. The same code performs well in Silverlight.
Jul 28, 2015 at 7:12 AM
I tried to track this down in the source yesterday but couldn't find anything suspicious. I will take a further look. Thanks for your quick answer.
Aug 4, 2015 at 8:14 AM
Edited Aug 5, 2015 at 8:56 AM
I found this article which mentions a limitation for Windows 8 to render shapes: https://rbrundritt.wordpress.com/2014/03/28/large-polyline-blurring-bug-workaround-for-windows-8/

I will take a look at the suggested workaround....

Edit: One of my colleagues found the following CodeProject Article which shows a Control thats support zoom for large lines: http://www.codeproject.com/Articles/85603/A-WPF-custom-control-for-zooming-and-panning

Maybe it is possible to use the technique described in the article for the map control.